In recent years, the recording density in the magnetic disk arranged in the magnetic disk device is being gradually developed to be higher. A slider is disposed in the magnetic disk device, wherein the slider is provided with a head used for the record and reproduction of data in the magnetic disk and is supported by a head assembly.
The head assembly is provided on a head actuator arm to form a head actuator arm which is rotatable by a voice coil motor (VCM). With VCM, the head provided on the slider can be controlled and located on any position of the magnetic disk.
However, in order to record the data in the magnetic disk in a higher density, it is necessary to highly precisely locate the head in the magnetic disk. Even if the head actuator arm is rotated through only VCM to locate the head, the location of the head in high precision is not enabled.
For instance, Patent Document 1 has disclosed the entire configuration of a head assembly having a conventional head rotating mechanism. The thin film piezoelectric element is bonded to the flexure disposed on the front end part of the head assembly. If the voltage is applied to the thin film piezoelectric element, the thin film piezoelectric element expands and contracts. Thereby, the slider rotates around the support projection and the head is displaced in a micro scale to be precisely located in the track.
In addition, a technical is proposed in Patent Document 2 that a counter balance is disposed in the symmetry axis of the gimbal part so as to improve the resonance frequency characteristic and also to perform the location in a high speed, wherein the gimbal supports the slider in such a manner that the slider is enabled to rotate around the support projection in a free style.